Wet and dry pump

ABSTRACT

Disclosed is a wet and dry pump, comprising: a housing having an inlet and an outlet of fluid; an impeller rotatably set in the housing; and a motor including a rotating shaft connected to the impeller, a stator fixed to an inner circumferential surface of the housing and having a damp-proof-processed winding coil therein, and a rotor fixed to an outer circumference of the rotating shaft with maintaining a certain gap with an inner circumference of the stator. Therefore, it can be advantageous to improve characteristics of power consumption and noise by making wet air or liquid pass through a passage between the stator and the rotor.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a wet and dry pump, and particularly,to a wet and dry pump capable of making wet air or liquid pass through aspace between a stator and a rotor by processing a motor to bedamp-proof.

2. Description of the Conventional Art

As shown in FIGS. 1 and 2, a conventional wet and dry pump includes: ahousing 110 provided with a cylindrical impeller cover 111 and acylindrical motor cover 112; an impeller 120 rotatably installed in theimpeller cover 112; a motor 140 installed in the motor cover 112 andconnected to the impeller 120 and a rotating shaft 130, for providing adriving force to rotate the impeller 120; and a cooling fan 170connected to the rotating shaft 130 and rotated by a rotation of therotating shaft 130 and thereby sucking a cooling air into the motorcover 102 to discharge it.

An inlet 113 for sucking fluid by an operation of the impeller 120 isformed at a central upper portion of the impeller cover 111, and aplurality of outlets 114 for discharging the fluid flowed in theimpeller cover 111 is formed at a circumference of the impeller cover111.

A suction opening 115 for sucking cooling air by an operation of thecooling fan 170 is formed at a central lower portion of the motor cover112, and a plurality of discharge openings 116 for discharging the airhaving performed a cooling operation to the outside are formed at acircumference of the motor cover 112.

The motor 140 includes: a stator 141 of a ring shape fixed at an innercircumferential surface of the motor cover 112; and a cylindrical rotor142 fixed at an outer circumference of the rotating shaft 130,maintaining a certain gap with an inner circumferential surface of thestator 141. According to this, the air sucked by the cooling fan 170discharges to the outside a heat generated from the motor 140 when theair passes through the gap between the stator 141 and the rotor 142.

A shielding wall 117 is installed between the impeller cover 111 and themotor cover 112. As a result, the fluid sucked by the impeller 120 cannot be flowed in the motor cover 112 and the cooling air sucked by thecooling fan 170 can not be flowed in the impeller cover 111 as well.

According to the aforementioned construction, when the motor 140 isoperated, the impeller 120 is rotated by the rotation of the rotatingshaft 130. As a result, fluid is flowed in the impeller cover 111through the inlet 113 of the impeller cover 111 and discharged to theoutside through the outlet 114.

Additionally, once the cooling fan 170 is rotated by the rotation of therotating shaft 130, the external air is sucked in the motor cover 112through the suction opening 115 and cools the motor 140 while passingthrough the gap between the stator 141 and the rotor 142, thereafterbeing discharged to the outside through the discharge opening 116.

In the aforementioned conventional wet and dry pump, since the shieldingwall 117 for shielding a space between an inner space of the impellercover 111 and an inner space of the motor cover 112 is installedtherein, the fluid flowed in the impeller cover 111 is prevented frombeing flowed toward the motor 140 and thereby the conventional wet anddry pump can pump wet air or liquid.

However, because the conventional wet and dry pump should have thecooling fan 170 for cooling the motor 140, power loss of approximately60˜70W is occurred, and noise of approximately 2˜3 dB isdisadvantageously increased thereby.

SUMMARY OF THE INVENTION

Therefore, an object of the present invention is to provide a wet anddry pump capable of improving a cooling efficiency of a motor byprocessing it to be damp-proof and thus by making wet air or liquid passthrough a space between a stator and a rotor, and capable of improvingcharacteristics of power consumption and noise by removing a separatecooling fan for cooling the motor.

To achieve these and other advantages and in accordance with the purposeof the present invention, as embodied and broadly described herein,there is provided a wet and dry pump, comprising: a housing having aninlet and an outlet of fluid; an impeller rotatably disposed in thehousing; and a motor including a rotating shaft connected to theimpeller, a stator fixed to an inner circumferential surface of thehousing and having a damp-proof-processed winding coil therein, and arotor fixed to an outer circumference of the rotating shaft withmaintaining a certain gap with an inner circumference of the stator.

The foregoing and other objects, features, aspects and advantages of thepresent invention will become more apparent from the following detaileddescription of the present invention when taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention andtogether with the description serve to explain the principles of theinvention.

In the drawings:

FIG. 1 is a front view showing a conventional wet and dry pump;

FIG. 2 is a longitudinal sectional view showing the wet and dry pumpshown in FIG. 1;

FIG. 3 is a front view showing a wet and dry pump according to thepresent invention;

FIG. 4 is a longitudinal sectional view showing the wet and dry pumpshown in FIG. 3;

FIG. 5 is a perspective view showing a partially cut stator in FIG. 3;

FIG. 6 is a graph showing respective power consumption of the wet anddry pump according to the present invention and that of the conventionalwet and dry pump, respectively in comparison therewith; and

FIG. 7 is a graph showing respective operation noise of the wet and drypump according to the present invention and that of the conventional wetand dry pump in comparison therewith.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings.

Referring to FIGS. 3 and 4, a wet and dry pump according to the presentinvention is comprised of: a housing 10 provided with a cylindricalimpeller cover 11 having an inlet 13 at a central upper portion thereofand a cylindrical motor cover 12 having a plurality of outlets 14 and 15along an outer circumference thereof; an impeller 10 rotatably installedin the impeller cover 11; and a motor 40 installed in the motor cover 12and connected to the impeller 20 and a rotating shaft 30, for providinga driving force to rotate the impeller 20.

The motor 40 includes: a stator 41 of a ring shape fixed to an innercircumferential surface of the motor cover 12; and a rotor 42 fixed toan outer circumference of the rotating shaft 30, maintaining a certaingap 50 with an inner circumference of the stator 41.

A brushless motor, particularly, a switched reluctance (SRM) motor ispreferably applied as the motor 40, and according to characteristics ofthe brushless motor, the rotor 42 has a characteristic of damp-proofing.

As can be seen from FIG. 5, the stator 41 is comprised of: a pluralityof bobbins 46 arranged as a ring shape and the each bobbin having a coil45 which is wound therein, wherein entire outer portion of the eachbobbin is molded (43) with a material such as a synthetic resin; and aplurality of conductors 47 connected to the plurality of bobbins 46,respectively, and exposed to the outside of the molding portion 43 at acertain interval along an inner circumference of the stator 41. As aresult, even although wet air or liquid passes through a space betweenthe stator 41 and the rotor 42, the coils 45 in the molding portion 43are shielded from the wet air or the liquid.

The molding portion 43 has a plurality of protruded portions 48 andrecessed portions 49 along an outer circumference thereof in order toform a cooling passage 51 through which fluid sucked by the impeller 10passes for cooling the motor 40. Namely, the protruded portion 48 of themolding portion 43 is fixed to an inner circumferential surface of themotor cover 12 via welding or other engaging means, thus the coolingpassage 51 is formed between the recessed portion 49 of the moldingportion 43 and the inner circumferential surface of the motor cover 12.

The plurality of outlets 14 and 15 formed at the motor cover 12 arecomprised of: a first outlet 14 formed at an upper side of the stator41, for first discharging the fluid flowed in from the impeller cover11; and a second outlet 15 formed at a lower side of the stator 41, forpassing fluid, which is not discharged to the outside through the firstoutlet 14, through the space between the stator 41 and the rotor 42 andthereafter for discharging to the outside.

The rotating shaft 30 can be protruded to the outside of the motor cover12. In this case, a bearing 17 is preferably installed between therotating shaft 30 and the motor cover 12.

Preferably, a guide member 22 for guiding the fluid flowed in by theimpeller 20 toward the motor cover 12 is installed between the impellercover 11 and the motor cover 12. In the embodiment of the presentinvention, the guide member 22 has a flat type of ring shape forming acurved surface toward the impeller 20.

Hereinafter, an operation of the wet and dry pump according to thepresent invention will be described.

First, once the rotor 42 is rotated by an electromagnetic interactionbetween the stator 41 and the rotor 42, the impeller 20 connected to therotor 42 and the rotating shaft 30 is rotated and thereby external fluidis flowed in through the inlet 13 of the impeller cover 11.

The fluid flowed in the impeller cover 11 is guided to the guide member22 to be flowed in the motor cover 12. A part of the fluid flowed in themotor cover 12 is discharged to the outside through the first outlet 14,and non-discharged fluid passes through the cooling passage 50 betweenthe stator 41 and the rotor 42 as well as the cooling passage 51 betweenthe inner circumference of the motor cover 12 and the outercircumference of the stator 41 in order to cool the motor 40.Furthermore, the fluid having performed the cooling operation for themotor 40 is discharged to the outside through the second outlet 15.

Hereinafter, effect of the wet and dry pump in accordance with thepresent invention will be explained with reference to FIGS. 6 and 7.

FIG. 6 is a graph showing a variation of power consumption based on adiameter of the inlet 13, namely, variation of suction capacity of thepump according to the present invention with the conventional pump,respectively. As shown in FIG. 6, it can be noticed that the pumpaccording to the present invention consumes power less than theconventional pump does because the cooling fan for cooling the motor hasbeen removed.

FIG. 7 is a graph showing noise measured in the conventional pump andthe pump according to the present invention, respectively. As shown inFIG. 7, it can be noticed that the pump according to the presentinvention is improved characteristics of noise in comparison with theconventional pump because the cooling fan for cooling the motor has beenremoved.

As stated above, the wet and dry pump according to the present inventioncan advantageously improve a cooling efficiency of the motor byprocessing it to be damp-proof and then making wet air or liquid passthrough a passage between the stator and the rotor.

Furthermore, the wet and dry pump according to the present invention canefficiently improve characteristics of power consumption and noise byremoving the cooling fan for cooling the motor.

As the present invention may be embodied in several forms withoutdeparting from the spirit or essential characteristics thereof, itshould also be understood that the above-described embodiments are notlimited by any of the details of the foregoing description, unlessotherwise specified, but rather should be construed broadly within itsspirit and scope as defined in the appended claims, and therefore allchanges and modifications that fall within the metes and bounds of theclaims, or equivalence of such metes and bounds are therefore intendedto be embraced by the appended claims.

1. A wet and dry pump, comprising: a housing having an inlet and anoutlet of fluid; an impeller rotatably set in the housing; and a motorincluding a rotating shaft connected to the impeller, a stator fixed toan inner circumferential surface of the housing and having adamp-proof-processed winding coil therein, and a rotor fixed to an outercircumference of the rotating shaft with maintaining a certain gap withan inner circumference of the stator.
 2. The pump of claim 1, whereinthe stator comprises: a plurality of bobbins arranged as a ring shapeand each bobbin having a coil wound therein, wherein an entire outerportion of the each bobbin is molded; and a plurality of conductorsconnected to the plurality of bobbins, respectively, and exposed to theoutside of the molding portion at a certain interval along an innercircumference of the stator.
 3. The pump of claim 2, wherein the housingcomprises: a cylindrical impeller cover having the inlet at a centralupper portion thereof and in which an impeller is arranged; and a motorcover to which the impeller cover is coupled, at which a plurality ofoutlets are formed along an outer circumference thereof, and which thestator is fixed to an inner circumference thereof.
 4. The pump of claim3, wherein a guide member for guiding fluid sucked by the impellertoward the motor cover is installed between the impeller cover and themotor cover.
 5. The pump of claim 4, wherein the guide member has aflat-type ring shape forming a curved surface toward the impeller. 6.The pump of claim 4, wherein the plurality of outlets are respectivelyformed at upper and lower sides of the stator.
 7. The pump of claim 3,wherein a cooling passage through which fluid sucked by the impellerpasses is formed between an outer circumference of the stator and aninner circumference of the motor cover.
 8. The pump of claim 4, whereinthe molding portion comprises a protruded portion protruding on an outercircumference of the molding portion to be fixed to an innercircumference of the motor cover, and a recessed portion recessed in theouter circumference of the molding portion to form the cooling passagewith the inner circumference of the motor cover.
 9. The pump of claim 1,wherein the motor is installed on a passage of the fluid flowed from theinlet to the outlet.